I have a Jacuzzi Esprit jetted tub that the on/off switch won’t stay on. I can push it manually but can’t get it to stay on.Holding the start button down doesn’t last.

SOURCE: jacuzzi tub on/off bezel wont hold switch down

I couldn't find the information you are asking for in the installation manual. I have included a link to the pdf page so you can print it out and look at it in print. On this particular question, I think I would give Jacuzzi a call. They can better answer you question without guessing.
http://jacuzzi.com/pdf/K272000.PDF?SELINSTMANS=K272000.PDF&goinst.x=15&goinst.y=8

SOURCE: jacuzzi nova 532 motor run's but won't stay running

If it has the little oval off/on button, it sounds like the control box or off/on button is bad. If you have access to the pump assembly, follow the pump power cord to the little black box (zip tied to a tube up high), this black box has a small cable that goes to the off/on button. unplug the pump from the box and plug the pump into the power outlet. it should run continuously. If it runs, you need a new control box or /offon button. Buy the off/on button first, as this button is prone to water getting into it, and costs less than the control box.

SOURCE: My Jacuzzi jetted tub has stopped working.

other than your switch , it could only be the moter or connection to it. always make sure you have enough water in the tub before turning it on or you'll ruin it.

SOURCE: Just drained jacuzzi hot tub and replaced

bleed pump check fuses and connections

SOURCE: I have a jacuzzi corner tub. The control panel

I would expect there is a Jacuzzi dealer in your town and I would guess he has parts. If you purchase parts locally, not only are you helping your neighbor but also, you will have the opportunity to pick his brain on tips to install.

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